VinFen, a large non-profit, canceled a $1 million contract with the committee to provide adult outpatient services to 800 Somerville adults, Dwyer said. The contract provided the mental health committee with roughly 20 percent of its budget and allowed it to operate other programs, such as a therapeutic program in city schools, that lost money.

Now, Dwyer said, the Somerville Mental Health Committee may not be able to provide services for "thousands of underprivileged people in Somerville" who rely on them.

Ward 5 Alderman Sean O'Donovan said VinFen has no Somerville facilities, making access to care even more difficult for patients, including some who have trouble leaving their homes and neighborhoods.

"We'll see the effects of this in the streets of Somerville," O'Donovan said. "I see this turning into a massive problem, 800 people who can't get their mental health treatment is significant. I think it could be devastating."

Alderman-at-Large Bill White said he expects aldermen to draft a resolution in support of the Somerville Mental Health Commission, asking VinFen to reconsider their move.

Dwyer said state Rep. Denise Provost and state Sen. Pat Jehlen, both Democrats of Somerville, spoke with VinFen officials in support of allowing the committee to keep the contract.